PDL-II install help

[Syntax]

Any advice on setting the gamma matches on the PDL II? When I had it up before we moved the vertical swr was very high. Someone also said to use a non metal section of mast that the beam actually mounts to.

Thanks

[1206FL]

Yes it can be mounted directly to a steel mast.

[MDYoungblood]

You can find the user and installation manual on CB Tricks. The two gamma's are set at different lengths, measurements are very critical on that antenna, best to measure twice. There shouldn't be a problem using a steel mast, anything other wouldn't support the weight.

3's

Greg

[MightyWhitey]

I've used the PDL-II and the Moonraker 4, and BOTH were mounted to a steel pipe in the top of the rotor. From what I remember, before putting the PDL in the air, I had it on it's back in the driveway (pointing up) for tuning. Got it as low as I could there then, then mounted as high as I could off the ground and did the best I could there before putting it on the roof. Used a tripod, a 10' piece of 2" water pipe in the rotor. That left it short enough I could still get to the gamma match to adjust. Great antennas! I still have an unused Moonraker IV in my garage that I picked up maybe 10 years ago, but never put up. Now it's just too much antenna for the location I'm in.

[231]

Any advice on setting the gamma matches on the PDL II? When I had it up before we moved the vertical swr was very high. Someone also said to use a non metal section of mast that the beam actually mounts to.

Thanks

That antenna won't likely be affected by a metallic support mast. I would however try and keep the length of the support mast between the boom and rotor a non-resonant length like 6', 10', etc. Around 8' is a resonant length and may possibly cause some interaction...to what extent is anyone's guess. But only being a 2 element quad it's best to avoid that.

As far as adjusting the gamma matches, I always did it on a mast just off the ground and set it for minimum SWR. The SWR's (both horizontal & vertical) should drop as you get the antenna in the air. I would probably consider downloading the instructions as Greg suggested from CB Tricks dot com, too. Doesn't cost anything.

231

[MDYoungblood]

And another thing is the rotor's location and type. The CDE (Cornell Dubilier) style rotors are the best, they can be placed anywhere from below the lowest point of the quad to up at the boom without affecting the SWR.
A regular small TV type rotor is offset so if placed up close to the boom of the quad the distance changes to the mast as the rotor turns, putting that type rotor below the quad puts a lot of strain on the rotor itself, they were made to carry the weight of a flat antenna close to the rotor, not 6, 8, or 10ft above it.
Coax is another thing that can change the SWR depending on where the loops (extra coax so the rotor can turn 360 deg) are located.

3's

Greg

[Syntax]

Do you guys know if the wire length that attach the elements the same for the Pdl II as they are four the Moonraker. When I initially set the PDL II up the element lengths were a bit longer then the instructions said to be. So when I extended the elements to make the wires snug and not droop the elements measured a bit more then what the directions said they should be.

Thanks for all the great responses.

[MightyWhitey]

The marks on the reflector wire are 9'6 1/2" for the PDL, 9'6" for the Moonraker. The tolerance is 1/16" on both. There isn't a specific element length mentioned, only the 9' 6 1/2" and 9' 6" marks respectively. Once the marks are matched up to the ends on the elements and tightened down, the elements are extended until the wire is taught, but not bowing.

If you do a Google search for "avanti pdl ii instruction manual" and "avanti moonraker 4 manual", you will have the pdf files for each of these antennas at CB Tricks dot com in your results. Those PDF files are the same instructions I used to build both antennas of mine.

[Syntax]

Thanks much.